"The FLIR overflight did not violate the accused’s constitutional right to be free from unreasonable search and seizure."

Another issue, targeting systems for reported powerful radar assaults could be based on radioactive isotopes or thermal imaging devices.

R. v. Tessling, 2004 SCC 67, 2004 3 SCR 432

Constitutional law — Charter of Rights — Search and seizure — Police using thermal imaging device to take “heat” picture of accused’s home from aircraft without warrant — Whether warrantless use of thermal imaging device violated right against unreasonable search and seizure — Canadian Charter of Rights and Freedoms, s. 8.

The RCMP used an airplane equipped with a Forward Looking Infra-Red (“FLIR”) camera to overfly properties owned by the accused. FLIR technology records images of thermal energy or heat radiating from a building. It cannot, at this stage of its development, determine the nature of the source of heat within the building or “see” through the external surfaces of a building. The RCMP were able to obtain a search warrant for the accused’s home based on the results of the FLIR image coupled with information supplied by two informants. In the house, the RCMP found a large quantity of marijuana and several guns. The accused was charged with a variety of drug and weapons offences. At trial, he unsuccessfully argued that the FLIR overflight was a violation of his right to be free from unreasonable search and seizure guaranteed by s. 8 of the Canadian Charter of Rights and Freedoms, and was convicted. The Court of Appeal set aside the convictions. The court found that the use of FLIR technology constituted a search of the accused’s home and, since it was done without a warrant, violated his s. 8 right. The court concluded that the evidence ought to have been excluded and the accused was acquitted on all charges.

Held: The appeal should be allowed. The FLIR overflight did not violate the accused’s constitutional right to be free from unreasonable search and seizure.